1. Field of Invention
The present invention relates to a semiconductor structure in integrated circuit (IC). More particularly, the present invention relates to a copper fuse of semiconductor structure for IC.
2. Description of Related Art
As the design rule of the semiconductor process approaches or is less than 0.18 xcexcm, copper gradually replaces aluminum as an interconnect in the metallization process since copper has lower resistance that can reduce RC delay. However, copper easily reacts with the oxygen in the surroundings to form a thin copper oxide on its surface, which leads to the failure of electrical contact. As a result, it is difficult to substitute copper for aluminum when forming a fuse in an IC as, in the IC industry, at the current line width.
The invention provides a structure of a copper fuse in an IC, by which structure RC delay is reduced.
As embodied and broadly described herein, the invention provides a structure of a copper fuse for an IC, which fuse includes two copper pads formed on a semiconductor substrate where the copper pads are isolated from each other with dielectrics. A metal line formed over the semiconductor substrate covers the two metal pads wherein one end of the metal line is connected to one of the two copper pads and the other end of the metal line is connected to the other of the two copper pads. A passivation layer formed over the semiconductor substrate covers the two copper pads.
It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed.